Installing hardwood, uneven floor

I am just about to start installation of hardwood however I have one problem. As you can see in the pictures there is uneven floor at the OSB joint at the master bedroom entrance. It seems like there is a beam right at the entrance and trusses are installed at the lower level if compared to the beam. There is probably 1/4" gap (at the most) between hardwood board and OSB subfloor. As I will be installing hardwood perpendicular to the trusses (marked in red), what can I do to reduce the bump?
Is sanding down the only way I can do it?